Abstract

Xanthomonas wilt caused by Xanthomonas campestris pv.musacearum (Xcm) is one of the most important constraints to banana production. The use of resistant banana varieties would be a long-term and cost-effective solution to control any pathogen. Therefore, identifying this pathogen resistant banana genotype is one of the basic requirements for effective management. The current study was therefore initiated to evaluate banana genotypes for resistance to banana Xanthomonas wilt. The experiment was conducted at Arsi University greenhouse from 2014 to 2015 GC. Banana and enset disease were collected and bacterial isolates were isolated and characterized based on different characterization tests. Twelve (12) banana genotypes were inoculated with three Xcm isolates (I1, I2 and I3) in a factorial experiment arranged in CRD with six replications. Disease assessment data was conducted and analyzed. Bacterial isolates were isolated and the identity of the isolated strains was confirmed as Xcm. The analysis of variance for incubation period, wilting incidence and disease severity revealed significant variations (p<0.05) among banana genotype and isolates. The results revealed that “Cadaba” genotype was found to have the lowest wilt incidence of 16.67%, severity index 15.07% and longest incubation period 5.28 and 9.33 weeks for initial and complete wilting respectively, moderately resistant to the pathogen and producers preferred for multiplication.  Butuza, Grandy nani, Robusta and Willams genotype were determined as moderately susceptible having wilting incidence of 21-30%. However, “Nijuru Genotype” showed the highest wilting incidence of 66.67%, severity index 38.78% followed by “Matooke that could be used as highly susceptible checks in future screening trail. Results also revealed that among Xcm isolates, isolate- I2 is the most aggressive, while isolate I1 is the least aggressive. As the current work revealed, the potential variation among banana genotype reaction to Xcm infection, genotype that showed moderately susceptible reaction should be further evaluated against Xcm.

Key words: Banana genotype, incubation period, wilt incidence, Xanthomonas campestris pv. musacearum.